Flexible container and method

ABSTRACT

A flexible container ( 100 ) has an internal volume ( 104 ) and an opening ( 102 ), and includes a first front panel ( 106 ), a second front panel ( 108 ), and a bottom panel ( 114 ) that is located between the first front panel ( 106 ) and the second front panel ( 108 ). The container ( 100 ) further includes two side panels ( 110  and  112 ), each side panel including a first flap ( 232 ) connected to the first front panel ( 106 ), a second flap ( 234 ) connected to the second front panel ( 108 ), and a third flap ( 236 ) connected to the bottom panel ( 114 ). A continuous sheet of material has a first fold ( 218 ) and a second fold ( 216 ), the first fold ( 218 ) separates a first front panel ( 106 ) and the bottom panel ( 114 ), and the second fold ( 216 ) separates the bottom panel ( 114 ) from the second front ( 108 ) panel. At least one seam ( 702 ) connects each first flap ( 232 ) and each second flap ( 234 ), and each third flap ( 236 ) is connected to at least one of the corresponding first flap ( 232 ) and second flap ( 234 ).

FIELD OF THE INVENTION

This invention relates to flexible containers, including but not limited to flexible containers formed from a sheet of material.

BACKGROUND OF THE INVENTION

Flexible bags made of paper are known. These paper bags are usually disposable bags that are used to carry various articles, including groceries. A typical paper bag is formed by attaching two opposite ends of a piece of paper to form a tube, and then folding one end in to form a cavity within the tube that is open on one end and closed on a folded end.

Paper bags are widely used because of their low cost of manufacture. Nevertheless, one disadvantage is their low strength. The strength of a paper bag is limited by either the strength and resistance to tears of the paper material, or by the strength of the attachment seams that form both a lengthwise seam of the tube, and all the seams used to attach the various folds and flaps that form the folded end. An additional disadvantage is the relative complexity of creating folded end in a mass production environment. Each of the folds on one end of a known paper bag may require a dedicated device to create and secure them, thus making their manufacture a time consuming process.

Accordingly, there is a need for a relatively inexpensive bag that has higher strength than a known paper bag, and is also easier to manufacture.

SUMMARY OF THE INVENTION

A flexible container that is suited for a mass production process, and that is stronger than the known flexible containers, is disclosed herein. The flexible container of one embodiment has an internal volume and an opening, and includes a first front panel, a second front panel, and a bottom panel that is located between the first front panel and the second front panel. The container further includes two side panels, each side panel including a first flap connected to the first front panel, a second flap connected to the second front panel, and a third flap connected to the bottom panel. A continuous sheet of material has a first fold and a second fold. The first fold separates a first front panel and the bottom panel, and the second fold separates the bottom panel from the second front panel. At least one seam connects each first flap and each second flap, and each third flap is connected to at least one of the corresponding first flap and second flap.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an outline view of a flexible container in accordance with the invention.

FIG. 2 is an outline view of a sheet of material that may be used to assemble the container of FIG. 1, in accordance with the invention.

FIGS. 3-5 are various stages of assembly for a flexible container in accordance with the invention.

FIG. 6 is an outline view of a flexible container having handles, in accordance with the invention.

FIG. 7 is a detail cross section view of a seam between panels in accordance with the invention.

FIG. 8 is a roll of material having segments arranged to make flexible containers in accordance with the invention.

FIG. 9 is a block diagram of a machine constructed to make flexible containers in accordance with the invention.

FIG. 10 is a flowchart for a method of mass producing a flexible container in accordance with the invention.

FIG. 11 is a flowchart for a method of making a flexible container in accordance with the invention.

DESCRIPTION OF A PREFERRED EMBODIMENT

The following describes an apparatus for and method of manufacturing and using a flexible container that is relatively inexpensive and has a higher strength than known flexible containers. A flexible container 100 is shown in FIG. 1. The flexible container 100 has panels on five sides and an opening 102 on a sixth side. The flexible container 100, when in an assembled configuration, may have a substantially rectangular shape. An internal volume 104 is formed when the container 100 is in an assembled condition. The internal volume 104 communicates with the opening 102. The container 100 has a first broad side panel 106, a second broad side panel 108, a first narrow side panel 110, a second narrow side panel 112, and a bottom panel 114. The first and second broad panels 106 and 108 are on opposing sides of the internal volume 104. Similarly, the first and second narrow panels 110 and 112 are on opposing sides of the internal volume 104. The panels 106, 108, 110, and 112 are connected along a lower rim 116 to the bottom panel 114, and form an upper rim 118 that defines the opening 102.

The first and second broad panels 106 and 108, along with the bottom panel 114, are advantageously connected to each other and are formed by an uninterrupted section of material or sheet. When the flexible container 100 contains a working load, for example articles that may be placed into the container for conveyance, the container 100 may effectively contain the working load and carry the working load with the first and second broad panels 106 and 108, and the bottom panel 114. The uninterrupted section of material making up these panels may advantageously give the container 100 superior strength.

The container 100 may be assembled or constructed from a sheet of material 200. The sheet 200 is shown in FIG. 2 in an unassembled condition. The sheet 200 may be any type of material, for example, paper, plastic sheet, Tyvek®, plastic mesh, etc. Assembly of the container 100 from the sheet 200 is advantageous because there is little to no material from the sheet 200 wasted during manufacturing of the container 100 by being cut away or removed from the sheet 200.

The sheet 200, when unfolded, includes a plurality of four incisions 202. The incisions 202 are located in symmetrical locations to each other on the sheet 200. The sheet 200 has a length, L, and a width, W. The length L of the sheet 200 may be divided into a first segment 204, a second segment 206, and a third segment 208, on either side of the sheet 200. The width W may be an uninterrupted segment on opposing edges of the sheet 200, with no incisions. A plurality of folds or creases may be formed in the sheet 200 during and/or after assembly of the sheet 200 into the container 100. A first, second, and third longitudinal creases 210, 212, and 214 may span the length L of the sheet 200, running substantially parallel to the segments 204, 206, and 208. A first and a second latitudinal creases 216 and 218 may connect two incisions 202 each, be aligned with the incisions 202, and span the width W of the sheet 200 that remains between the incisions 202. A first, second, and third segment 220, 222, and 224 may be formed on either edge of the sheet 200 spanning the width W.

The sheet 200 may advantageously be segmented into nine panels that are defined between the incisions 202 and/or the creases 208, 210, 212, 214, 216, and 218. A first front panel 226 may be defined between the segment 222, the creases 210, and the crease 216. Similarly, a second front panel 228 may be defined between the segment 222 on an opposing edge of the sheet 200, the creases 214, and the crease 218. A bottom panel 230 may be defined by the creases 212, 216, and 218, and be located between the panels 226 and 228 along the length L of the sheet 200. Two first side panels 232 may be adjacent to the first front panel 226, one on either side thereof, and defined by the segments 220 and 224, the creases 210, and the incisions 202. Similarly, two second side panels 234 may be adjacent to the second front panel 228, one on either side thereof, and defined by the segments 220 and 224, the creases 214, and the incisions 202. Two third side panels 236 may be defined by the incisions 202, the creases 212, and the segments 206, and be located adjacent to the bottom panel 230, one on either side thereof, and between the side panels 232 and 234 along the length L of the sheet 200.

A method of assembling the container 100 from the sheet 200 is shown in FIGS. 3-5. The sheet 200 is folded once along the incisions 202 and the crease 218 to bring the panels 228 and 234 in an upward direction, or, to form an angle with respect to the bottom panel 230. The sheet 200 may be folded once more along the incisions 202 and the crease 216 to bring the panels 226 and 232 in an upward direction or angle with respect to the bottom panel 230. The panels 234 may then be folded inward along the creases 214 and form an angle with the panel 228. The panels 236 may then be folded along the creases 212 to form an angle with the bottom panel 230. All these angles may advantageously be about 90 degrees when the folding of any panel along any crease has been completed. When the panels 226, 228, 234 and 236 have been folded, the panels 232 are folded along the creases 210, as shown in FIG. 5, to complete a shaping operation of the sheet 200.

When the shaping operation of the sheet 200 has been completed, a bonding operation may be performed to connect some panels to each other and form the container 100. Panels may be connected to each other in various fashions, which fashions may depend on the type of material used for the sheet 200. Attachment methods that may be used include stitching, gluing, riveting, thermally or vibrationally welding, and so forth. In a preferred embodiment the material used for the sheet 200 may be Tyvek® Type 10 or other types, manufactured by the DuPont Corporation. Adhesives compatible with this material are known in the industry, and any suitable material may be used to adhere panels formed from a sheet of Tyvek® to each other. In a preferred embodiment, the panels of the container 100 are bonded using natural product adhesives based on starch, dextrin, casein, or animal by-products, which are preferred over synthetic-based adhesives. Some polyurethane adhesives provide optimum adhesion (lap and shear), flexibility and water resistance.

A bonding configuration for the container 100 is shown in FIG. 6, and a detailed cross sectional view along a plane A-A at a panel interface is shown in FIG. 7 (with a thickness of the panels shown exaggerated for clarity). The panel 236 may overlap panels 232 and 234 along a region adjacent to the lower rim 118. The panels 232 and 234 may overlap over a region, B, along an entire height, H, of the container 100. A first bead of adhesive 702 may be deposited between the panels 234 and 236, and a second bead of adhesive may be deposited between the panels 232 and 236. The first and second beads of adhesive 702 and 704 may be manually or mechanically deposited before, during, or after the shaping operation of the sheet 200. The beads of adhesive 702 and 704 may span the entire height H of the container 100. Above a height, h, where all three panels 232, 234, and 236 overlap, the beads 702 and 704 may be deposited directly between the panels 232 and 234. Alternatively, one of the beads 702 and 704 may be discontinued at or beyond the height h of the container 100, and the other may continue all the way to the top of the container 100. Instead of adhesive, a stitch 705 may be applied to connect panels to each other. Any method of seaming panels to each other that is appropriate for connecting the material of the panels may also be used. Adjacent to the upper rim 118, there may be a handle 602 attached to the first front panel 106, or alternatively, a handle cutout or slit 604 may be formed therein.

A design for the container 100 is advantageously well suited for a mass production operation. A plurality of preconfigured sheets 800 may be part of a roll of material 801, as shown in FIG. 8. Each sheet 800 may be configured similar to the sheet 200 described above, having four incisions 802 pre-cut therein, and having a length, L′, predefined therein as a length of material from the roll 802 defined by a series of perforations 803 formed therein. Altenatively, a cutting operation may advantageously be used to form the perforations 803 and the incisions 802 into a continuous roll or material. The roll 801 may have a width, W′. The roll 801 may be arranged in operable communication with a machine 900, as shown in FIG. 9. The machine 900 may be configured to admit one sheet 800 at a time. The sheet 800 may be pulled into the machine 900, and cut from the roll 801. The sheet 800 may be folded as described above, and beads of adhesive may be deposited on formed panels, as described above, to form a container 901.

When in the machine 900, the sheet 800 may undergo folding operations that are accomplished by retention and deformation or folding of panels by a plurality of carriages 902 attached to the machine 900. The machine 900 may have a feeding and portioning device 904 that straightens and portions each sheet 800 before each sheet enters the carriages 902. Referring to FIG. 9, when a sheet 800 is located between the carriages 902, it may be folded as denoted by the arrows around a central core 906, thus accomplishing, for example, folding of the first and second front panels of the container 100 as described above. Other carriages (not shown) may perform additional folding operations sequentially to complete formation of the container 100. The carriages 902 may advantageously be rotateably connected to the machine 900 and may also have an adhesive deposition system, as well as a vacuum sheet-retention system attached or integrated thereon. A “sheet retention system” may be any known method of retaining sheet material to a machine element that includes, for example, vacuum or electrostatic retention pressures that are applied between the machine element and the sheet. Once the container 100 is complete, the core 906 may serve as an ejection carriage that carries the completed container 100 from the machine 900 and into a collection, stacking, or packaging device (not shown).

The flexible container 100 is advantageous when compared with flexible containers that are currently available, because it is able to withstand conveyance of heavier loads for a same material and thickness used to make the container as compared to a known flexible container of a similar size. The container described herein may be capable of an increased load carrying capacity of up to 80% when compared to a typical container. Moreover, a container in accordance with the invention is well suited for mass production because there are limited cuts and removal of material from a forming sheet. Many known designs for flexible containers entail creation of a tube shape out of a sheet of material, followed by various cutting and folding operations to form the tube into a cylinder, and finally fold one end of the cylinder to form a container. These operations are both time consuming and present challenges for a fast paced manufacturing operation. In contrast, a container as described herein may be formed out of a sheet of material allowing use of a roll, there is no removal of material from the sheet required, a number of incisions may be pre-cut into the sheet or may be cut into a forming machine, and there are merely 4 folding operations, 2 panels each, that need to be completed to form the container. These features enable a cost and time effective production operation to be employed.

A flowchart for a method of producing a flexible container is shown in FIG. 10. A roll of material may be unrolled at step 1002. The material may include a plurality of segments, each segment including a main sheet, four large flaps, and two small flaps. Each of the four large flaps and each of the two small flaps may be connected and be part of the main sheet of material. A segment from the roll of material is separated and may be admitted into a machine at step 1004. In an alternative embodiment, the sheet material may be whole, and an optional cutting operation may form incisions into a sheet length that is portioned.

The machine may be used to fold the main sheet once to form a first side panel, and once more to form a second side panel and a bottom panel at step 1006. These panels may enclose an interior volume on three sides. Each of the four large flaps and the two small flaps may be folded around the interior volume at step 1008. Two of each of the large flaps and one of each of the two flaps are may be located adjacent to each other. The two of each of the large flaps and the one of each of the two flaps are connected together to form the flexible container at step 1010. The flexible container now enclosed five sides of the interior volume. The flexible container may be ejected from the machine at step 1012.

A flowchart for a method for making a flexible container is shown in FIG. 11. A plurality of incisions may be made in a sheet of material at step 1102. The incisions may be arranged in pairs, each pair may be along a line, and each line may be perpendicular to an edge of the sheet. At least two lines may be parallel. A first panel and a second panel of the sheet are folded along each of the lines at step 1104. The first panel and the second panel may be folded to oppose each other on the same side of the sheet. A first flap, a second flap, and a third flap are turned-in on each of two sides of the sheet to close each of the two sides at step 1106. Each first flap may be connected to the first panel, each second flap may be connected to the second panel, and each third flap may be connected to a bottom panel. The bottom panel may be connected to the sheet and defined between the at least two lines that are parallel. The first flap may be seamed, adhered, or otherwise attached to at least one of the second flap and the third flap at step 1108.

The flexible container disclosed herein is well suited as a conveyance for manual transportation for articles, but may also advantageously be used as a toy platform for small animals, for example, felines. A container constructed in accordance with the invention is more resilient and robust, and better suited to withstand use as a toy by an animal. Various add-on toys may be used in conjunction with the flexible container described herein. For example, a toy article may be connected to a distal end of a string. The string may be attached through, for example, a hole formed in one of the panels of the container, to allow a feline to play with the toy article both inside the interior volume of the container, as well as outside the opening.

The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope. 

1. A container having an internal volume and an opening, comprising: a first front panel, a second front panel, and a bottom panel disposed between the first front panel and the second front panel; two side panels, each side panel comprising a first flap connected to the first front panel, a second flap connected to the second front panel, and a third flap connected to the bottom panel; wherein a continuous sheet of material has a first fold and a second fold, wherein the first fold separates a first front panel and the bottom panel, and wherein the second fold separates the bottom panel from the second front panel; wherein at least one seam is disposed between each first flap and each second flap, and wherein each third flap is connected to at least one of the corresponding first flap and second flap.
 2. The container of claim 1, further comprising a first handle disposed on the first side panel, and a second handle disposed on the second side panel, wherein the first handle and the second handle are disposed adjacent to the opening.
 3. The container of claim 1, further comprising a first slit in the first side pane, and a second slit in the second side panel, wherein the first slit and the second slit form a first handle and a second handle respectively.
 4. The container of claim 1, wherein the material is at least one of Tyvek®, paper, fabric, and plastic.
 5. The container of claim 1, wherein the at least one seam is a plurality of stitches.
 6. The container of claim 1, further comprising an amount of adhesive disposed between each first flap and each second flap to form the seam.
 7. The container of claim 1, further comprising a second seam disposed between each first flap and each second flap, wherein the second seam has a length, and wherein the length is disposed along an entire length of the container, spanning between the bottom panel and a rim of the opening.
 8. A method for mass producing a flexible container, comprising the steps of: unrolling a roll of material, wherein the material comprises a plurality of segments, each segment comprising a main sheet, four large flaps, and two small flaps, wherein each of the four large flaps and each of the two small flaps is connected to the main sheet; separating a segment from the roll of material and admitting same to a machine; using the machine to fold the main sheet twice to form a first side panel, a second side panel, and a bottom panel, said panels enclosing an interior volume on three sides; folding each of the four large flaps and the two small flaps around the interior volume, wherein two of each of the large flaps and one of each of the two flaps are disposed adjacent to each other; connecting the two of each of the large flaps and the one of each of the two flaps together to form the flexible container, said flexible container enclosing five sides of the interior volume; and ejecting the flexible container from the machine.
 9. The method of claim 8, wherein each segment further comprises two handles, wherein each handle is disposed on a same side of the main sheet, and wherein each handle is disposed on opposite distal ends of the main sheet.
 10. The method of claim 8, wherein each segment further comprises two slits, wherein each slit is disposed on opposite distal ends of the main sheet.
 11. The method of claim 8, wherein the step of connecting is accomplished by use of at least one of stitching, gluing, thermally welding, and buttoning.
 12. The method of claim 8, further comprising the step of attaching a pair of handles to the main sheet.
 13. The method of claim 8, wherein the steps of folding are accomplished by a plurality of machine carriages.
 14. A method of making a flexible container, comprising the steps of: making a plurality of incisions in a sheet of material, wherein the incisions are arranged in pairs, wherein each pair is a line, wherein each line is perpendicular to an edge of the sheet, and wherein at least two lines are parallel; folding a first panel and a second panel of the sheet along each of the lines, wherein the first panel and the second panel are folded to oppose each other; turning in a first flap, a second flap, and a third flap on each of two sides of the sheet to close each of the two sides, wherein each first flap is disposed on the first panel, wherein each second flap is disposed on the second panel, and wherein each third flap is disposed on a bottom panel, the bottom panel disposed on the sheet and defined between the at least two lines that are parallel; seaming the first flap to at least one of the second flap and the third flap.
 15. The method of claim 14, wherein the plurality of incisions includes four incisions, wherein the four incisions define a first pair and a second pair, wherein a first line is defined by the first pair of incisions, and wherein a second line is defined by the second pair of incisions.
 16. The method of claim 14, wherein the step of turning is accomplished by at least one carriage that is operably connected to a machine.
 17. The method of claim 14, further comprising the step of removing the sheet of material from a roll.
 18. The method of claim 14, wherein the step of seaming includes at least one of depositing at least one bead of adhesive, sewing, and riveting.
 19. The method of claim 14, wherein the sheet of material is made of Tyvek®.
 20. The method of claim 14, further comprising the step of attaching at least one handle to the first panel. 